变生锆石对稀土矿化的指示意义

INDICATIVE SIGNIFICANCE OF VARIOZIRCON TO THE MINERALIZATION OF REE MINERALS

锆石是各类岩石中普遍存在的一种常见的副矿物,但不同物理化学条件下产出的锆石其标型特征各有差别。本文根据吉林省及内蒙古境内某些碱性岩及碱性花岗岩体中锆石的研究,结合了其他地区有关资料编写而成。文中提出了有关含稀有、稀土矿产的岩体中锆石的标型特征及其成矿标志,藉此探讨确定矿化与非矿化岩体的各项准则。

Zircon is usually present in alkaline rocks and alkaline granites. The ty-pomorph of the zircon in the mineralized body are different from those of the zirco in the nonmineralized body. Therefore, the typomorphs of zircon are important signs to exploreREE minerals and to evaluate their significance of in industry.The typomorph of zircon in mineralized body are as listed below.1. The crystals of zircon are bipyramid with a {111}form, or short prismatic crystals made of {111}and {110} .Their elongate coefficient is less than2. Moreover,zircon makes up globular or botryoidal aggregates.2. Crystals of zircon usually contain REE within a range from o.n% to n%.3. The physical properties of zircon show a wide range of variation. Their hardness, refractive indices and specific gravity are lower than the averages, but magnetic susceptibility, dielectric coniant are higher.4. The luminescence of zircon is weaker, or no luminescence.5. The amount of zircon in minerali zed body increases and is generally higher than 0.5g/T.